Torque unit



Odi.k 1, 1957 J, J, GvElER EVAL TORQUE UNIT 4 Sheets-Sheet 1 Filed July 27, 1955 l r INVENTOR. JJM/J Gf/ER v By ne L. Su/vqu/sr Oct. 1, 1957 I J.J.GE1ER ETAL TORQUE UNIT 4 Sheets-Sheet 2 Filed July 27. 1955 T 5. S E www yN NHG, MR m o m WGW T JS @,A NL H .wm Y B Oct. 1, 1957 J, J, GElER ETAL 2,808,033

TORQUE UNIT Filed July 27, 1955 4 Sheets-Sheet 3 l :gg

I E i@ TRO/(E l 5 TROKE l-iLl/ Z? @fw i @ig i STROKE 1 VENToRs JOHN Cif/ER Y/.E L. Sa/vopu/sr A TTOR NE YS.

J. J. GEIER ETAL TORQUE UNIT 4 Sheets-Sheet 4 INVENTORSl JOHN J. GE/ER BY Y/.E L. Su/vDU/.sr

ATTORNEYS.

Oct. 1, 1957 Filed July 27, 1955 United States Patent C;

TORQUE UNIT John J. Geier, Clinton, and Lyle L. Sundquist, Fort Lee, N. J., assignors to Hydro-Torque, Inc., Freeport, N. Y., a corporation of New York Application July 27, 1955, Serial No. 524,748

14 Claims. (Cl. 121-33) This invention relates to devices for converting reciprocating` motion into rotary motion and relates more particularly to portable torque-applicator devices which are fluid-pressure actuated and are of utility especially as wrenches for running up or removing nuts or bolts, or as driver units for twist drills, bits, screws and the like.

It is an object of this invention to combine, in a torque applicator device, an axially reciprocable drive means and a rotatable torque applicator shaft in such fashion as to enable the obtainment of a substantially higher average shaft torque output per unit of stroke of the reciprocable drive means than has heretofore been obtainable with such devices.

It is another object of this invention to enable the obtainment in a torque applicator device combining an axially reciprocable drive means with a rotatable torque -applicator shaft, of high shaft torque output with short stroke of the reciprocable drive means.

It is a further object of this invention to provide a lluid-pressure-actuated torque applicator device in which a rotatable torque applicator shaft is driven unidirectionally, but at relatively low speed, by relatively high speed, fluid-pressure-actuated axially reciprocable drive means and is capable of delivering its torque in both directions of movement of the drive means.

It is a still further object of this invention to provide a torque applicator device of the nature aforesaid in which the output torque of the rotatable torque applicator shaft may be taken from either end of the shaft.

It is yet another object of this invention to provide a new and improved hydraulically actuated torque applicator which is compact and easily transportable and is capable of delivering a high output torque either in a clockwise or counterclockwise direction as may be required.

It is also an object of this invention to provide a new, useful and improved hydraulic wrench.

Other and further objects of this invention will appear from the following description, the accompanying drawings andthe appended claims.

To the accomplishment of the foregoing ends and objects, there is provided in accordance with this invention a shaft of cylindrical contour, sometimes hereinafter referred to as a torque shaft, which is mounted for rotation on its cylinder axis and serves as a means for applying torque at either of its ends to a nut, bolt, drill, bit or other device to be rotated. Drive means, including a piston mounted for reciprocation lengthwise of the torque shaft cylinder axis, are provided for drivingthe torque shaft at each stroke so as to impart thereto a motion of rotation which is in the same direction, for each stroke of the piston. To this end therefore, the drive means also includes a pair of motion-converting coupling members mounted on the torque shaft and spaced from each other by the piston, and serving alternately automatically tov p 2,808,033 Patented Oct. 1, 1957 by leach coupling member between the piston and the torque shaft is of a nature such as to convert linear m0- tion of the piston into rotary motion of the drive shaft. Moreover, by reason of the alternating connections provided by the coupling members the motion of the piston in either direction in its stroke will always result in a unidirectional rotation of the torque shaft which is clockwise as viewed from one end of the shaft and counterclockwise from the other.

The stroke of the piston is preferably relatively short and the extent or degree of rotation of the torque shaft for each stroke of the piston is preferably commensurately small. Hence, a relatively high ratio of piston strokes per unit of rotation of the torque shaft is obtainable and, by the application of a relatively high fluid-input pressure to the piston, a higher than average torque output at the torque shaft ends per unit of piston stroke, will result.

Reciprocation of the piston is effected, preferably by hydraulic pressureV applied first to one side and then the other through the action of `suitable switching valve means actuated automatically at the end of each stroke to effect the necessary pressure, and, in turn, motion reversal.

In the accompanying drawings which form part of the instant specification and in which like numbers refer to like parts through the several views:

Fig. 1 is a view in section of a double ended torque wrench embodying this invention, the view being taken along the central medial plane of the wrench;

Fig. 2 is a view in side elevation of the torque shaft and motion converting coupling members of the device of Fig. l;

Fig. 3 is a view in section taken along the line 3-3 of Fig. l;

Fig. 4 is a view in section taken along the line 4--4 of Fig. l;

Fig. 5 is a view in side elevation of the piston-torque shaft assembly of Fig. l;

Fig. 6 is a fragmentary view in section taken along the line 6 5 of Fig. l, showing details of the valving mechanism;

Fig. 7 is a fragmentary view in section taken along the line '7 7 of Fig. 6;

Fig. 8 is a fragmentary view in section taken along the line 8 8 of Fig. 6;

Figs. 9, 10 and ll are developed views of the pistoncoupling assembly of Fig. l showing the relationship of these parts in stages of the piston stroke;

Fig. l2 is a view in section of a modified form of torque wrench embodying this invention, the view being taken along the central medial plane of the device;

Fig. 13 is a view in side elevation of the piston-torque shaft assembly of Fig. l2;

Fig. 14 is a view in section taken along the line 14- i4 of Fig. l2; and,

Fig. l5 is a view in section of one of the motion converting coupling members of the device of Fig. l2, the view being taken along the central medial plane of the coupling member.

Referring now to the embodiment of the invention shown in Figs. l to l1 inclusive, a piston 1 is mounted for reciprocation in a cylinder 2. O'il or other suitably working uid for driving the piston 1 is adapted to.be supplied as by a pump (not shown) and under suitable pressure to a valve chest 3 as by a feed pipe 4. A rotary two-position cylindrical valve 5 is journalled in the valve chest 3 for oscillation between a pair of terminal positions in each of which the working iluid may flow from the valve chest to the bore of the cylinder 2, for reciprocating the piston.

The valve 5 is provided with an axially extending feed chamber 6 which is closed at one end and is open at the other to receive working fluid supplied to the valve chest. The valve 'S is also provided intermediate the ends of the chamber 6 with a pair of radially extending distributing passages 7 `and .8, respectively. Thepassages 7 and 8 serve to conduct workinguid 'from the chamber 6 either to one or Vthe other of a pair of diametrically opposed header compartments 9 and ltllformed in the valve chest. AThe'header compartments,are,in'turn, connected by Apassageways `1-1 and 12, respectively, with the bore of the cylinder "2 at ,opposite sides of thepiston 1. r-T he angle of Yinclination of the inlet passages 7 and 8 to each other Vis such that positioning the valve '5 .to place `the passage 7, forexample, in communication vwith the `header 9, as shown in Fig. '7, will cause Lthe passage `8 `to .be sealed-ofi? by the opposing, journalsurface l13 of the valve chest. lfhusgwith thepiston nl at the end of its stroke, as 4in Fig. 1 working `fluid :may flow from the chamber 6 via-the.passage A7, Vheader compartment 9 and passageway.'11 to Lthe `right'hand face `of thepiston, as viewed in-Fig. 1, so asto drive thepistonto the left. It follows that switching of the valve by rotating the valve counterclockwise, as Iviewed in Fig. 7, to a position in which thetdistributingpassage Sis placed in communication with the header compartment 10, will cause the passage T7 to .be sealed-off. Switching of the valve 5 is adapted tobe accomplished automatically at the end of each stroke, by means of a Vspring-:pressed snap-action toggle 14 flexibly connected at its one end tothe piston 1 and at its other to the valve 5, as shown in Fig. 1. Both the valve-chest 3 and cylinder 2 are -suitably recessed to provide a tapered .chamber 15. dimensioned to permit the toggle freely tooscillate betweenits terminal positions.

The valveS is also provided with an axially-extending by-'pass chamber 16 which 'is partitioned off at one end from the chamber 6. It is also provided with a pairof radially extending {by-pass passages r17 and 18, respectively, intermediate the ends of the chamber 16, and with a plurality .of radially `extending discharge passages 19 at the other end of the chamber `16. Four such Vdischarge passages `are shown in Fig. 8. Y

It will be understood that as `the piston -1 moves in either direction inthe bore `of the cylinder 2, low pressure .working fluid at the downstream or low pressure side of the piston, must be evacuated therefrom at the same time that vhigh pressure working fluidis being supplied'to the upstream or high pressure side ofthe piston. The .passageways 1'1 and 12 -serve reversibly as supply and discharge conduits for conducting `working duid between .the cylinder Ybore and the respective header compartments 9-and 10,.,and the by-pass passages 17 and 18 serve to conduct working fluid discharged intothe header compartments from the cylinder bore, into the by-pass compartment 16. Accordingly, lthe by-pass passages 17 and 18 are inclined'toeach other at a suitable angle and are suitably `angularly offset `relative to lthe distributing passages 7 and 8, so that while high pressure working duid-is being supplied to either oneiof `the header cornpartments 9 and 10 from the feed chamber '6, evacuated working fluid `may continuously escape from the other header compartment into the by-pass compartment 16 with its discharge passages 19.

The discharge passages 19 terminate each :inta com-- mon annular `sump -20 formed -in thevalve chest 3 and surrounding the `valve 45. A ,passageway 2,1 in the valve chest 3 serves to conduct the .evacuated working fluid from ithesump 3 tothe outside of'the'valve chest, and may be coupled,ias by a.pipe 22, to an accumulator (not shown) for Arepressuring -and recycling in the pumping system.

T he=piston .1 is symmetrical about a plane `normal to its stroke axis, centrally apertured and is provided 'with a hollowtubular piston rod 23 :extending in oppositeldirections for equal distances fromthe piston 'plane ,ofsymmetny. Thus, as 'viewed in iFig. 1, ythe pistoni-rod 23 is made .up of right-'handiand left-hand portions 24and 2S heads are flanged on their inside faces to provide in the cylinder bore right-hand and left-hand tubular bearing flanges, 28 and 29, respectively, which serve as extended l tubular bearing surfaces for the rod portions 24 and 25,

respectively, and minimize leakage of working fluid between the `piston rod and cylinder heads, from the cylinder bore. ln accordance with this 'feature of .the invention, the piston 1 is of a configuration to provide in-its opposite faces annular recesses 30 and 31, respectively, in which the sealing flanges 28 and 29, respectively, are telescopically received at the extremes-ofthe piston stroke.

T he cylinder heads are also flanged on their respective outer faces to provide externally right-hand and lefthand tubular spline anges 32 and 33,respectively, whose inner circumferential,peripheries are, respectively, of a contiguration'to provide `spline'lands 34 and 35, respectively, which mate with spline grooves 36 and 37, 'respectively, in the piston rod 4portions 24 and 25, respectively. Thus, the motion rof the .piston and its rod is confined toflinear reciprocation relative to the cylinder 2, and spline flanges 32 and 33.

The external bearing tianges 32 and 33 are provided with vent openings 38 and `39, respectively, in which vent lines 40 and 41,'respectively, are secured for the escape of such yworking fluid as may `leak between the piston rod and the cylinder head apertures into the respective bores of .the bearing flanges. Advantageously, the cylinder head 26 with its `spline flange 32 maybe detachably `coupled to thecylinder 2, as by bolts 30', to` permit assembly and disassembly of the parts. The bores of .the tubular spline flanges 32 and 33 are-capped by closure members 42 and 43 detachably firmly secured to the flanges 32 and 33,respectively, as by sets of'bolts 44 and 45, respectively.

The closuremembers 42-and 43 are centrally apertured to provide .journal'bearing surfaces 46 and 47, respectively, which are coaxially aligned with each other-and with the axis of reciproeation of the piston 1. Advantageously, the bearing surfaces 46 and 47 may be provided by replaceable bearing inserts 48 and 49, respectively, seatedin the respective closure members and providing separate thrust bearing surfaces 50 and 51, respectively, for a purpose which will more `fully appear hereinafter.

A torque shaft 53 of cylindrical contour is disposed within-the boreof the piston rod 23 in sliding tit relation to the piston rod. The torquezshaft isof a configurationto provide a pair of lesser diameter cylindrical end` portions 54 and 55 and is of a length such that it extends at each end a suitable distance beyond the end closure `members 42 and 43. The outer `extremity of each `end `portion is formed toprovidea torque applicator head of aconfigurationadapting-it for operative connection to whatever device is to be torque driven. As here ,preferably embodied,`the extremities yof the end .portions 54 and 55 are'in the form of `four-sided bits 56 and 57 adaptedfor use to drive a bolt havinga recessed head, such, for example, as the bolt 59 indicated by dash-dot lines inFig. l.

The torque shaft is journalled forrotation-in'the `bore of the pistonrod23 by means of` the end-portions 54 and journalled on v.the bearing surfaces 46 and 47, respectively.

Motion-converting coupling members ldesignated `generally by the numerals 60 and 61 fare mounted on the torqueshaftend portions .54 and '5i-respectively, forconverting `the linear reciprocating ymotion of the driving piston 1 into unidirectional rotary'rnotion of the torque shaft. The coupling members-60-and '61 areof identical constructionfand `their coaetion -with the-torque shaft 53 is ythe same forone as for'the other.

The vcoupling rmembers `6l) Land y61 ,are of `cylindrical contour andoffan external diameter preferably slightly less than that portion of the torque shaft 53 between the lesser diameter cylindrical end portions 54 and 55 so as to be receivable within the bore of the tubular piston rod 23. Each member is apertured from end to end longitudinally of its cylindrical axis so as to permit of the members 60 and 61 being journalled for limited angular movement on the torque shaft end portions 54 and 55, respectively. The member 60 is of a length axially to fit easily, but not snugly, between the right hand end, as viewed in Fig. l, of the larger diameter portion of the torque shaft and the opposing thrust bearing surface 50 of the bearing insert 48, a similar arrangement obtaining between the coupling member 61 and the thrust bearing surface 51 at the other end of the torque shaft. The members 60 and 61 are also of a configuration to provide a pair of coaxial recesses 62 and 63, respectively, for the reception of a pair of coiled restoring springs 64 and 65, respectively, which are constructed and arranged to exercise respective restoring forces on the respective coupling members upon the torque shaft being angularly displaced relative to the coupling. `Thus, assuming the coupling member 60 to be held against rotation and the torque shaft 23 to be angularly displaced in `a clockwise direction as viewed from the right-hand end in Fig. 1, the coil spring 64 will be wound up and tend to rotate the coupling member 60 clockwise if the latter is released. At the other end of the torque shaft, the same rotation of the torque shaft will be counterclockwise as viewed from the left-hand end in Fig. l, and the coil spring 65 will be wound up and tend to rotate the coupling member 61 counterclockwise upon release of the latter. To this end, therefore, the respective ends of the Vcoil spring 64 are seated in suitable recesses 66 and 68 in the coupling member 60 and torque shaft 53, respectively and the ends of the coil spring 65 are seated in suitable recesses 67 and 69 in the coupling member 61 and torque shaft 53, respectively. v f

The recessed end of the coupling member 60 is of a configuration to co-act with the opposing end of the torque shaft 53 to permit limited angular displacement of the torque shaft relative to the coupling member. As here preferably embodied, the recessedend of the coupling member 60 vis provided with a circular row of driving teeth .70- and the 4opposing end of the torque shaft is provided similarly with a circular row of driven teeth 72, the teeth in each row extending into the inter-tooth spaces in the other row and the teeth in -the-respective rows being requally spaced apart from each other circumferentially a distance suicient to permit the requisite limited angular displacement of the torque shaftrelative to the coupling member 60. Similarly, the recessed end of the coupling member 61 and the opposing end of the torque shaft 53 are provided with the circular rows of driving and driven teeth 71 and 73, respectively,I in a corresponding relationship. It will be apparent from Figs. l and 2 that the driving teeth of each coupling member are normally held againstthe driven teeth of thev torque shaft but that by reason of the spacing between the teeth in each row,y either coupling member maybe held against rotation and still permit the other to impart rotation to the torque shaft over a limited angular .distance without interference.

A set of rollers or cam followers 74 is carried by the coupling member 6) and a corresponding set 75 by the coupling member 61. The rollers of each set are arranged in pairs of ,diametrically opposed rollers, the pairs of each set being equally angularly offset from each other.'v

The rollers74 are journalled individually on individual axles of a set of radially extending axles 76 carried fixe'dly by the coupling member 60 in suitable apertures therein. Similarly, the rollers 75 of the coupling member 61 are individually journalled on corresponding individual axles 77. Advantageously, the circumferential periphery of each of the coupling members 60 and 61 may be suitably recessed to provide individual recesses 78 for the rollers 74 and like recesses 79 for the rollers 75. In this way the rollers may be axially dimensioned to obtain a structural strength adequate yto carry safely the maximum loading to be imposed thereon.

For the purpose of rotating the coupling members 60 and 61 alternately so as in turn to rotate the torque shaft always in the same direction, the tubular piston rod portions 2.4 and 25 are of a configuration at their free ends to provide at each such end a set of camming surfaces for alternate driving engagement with and disengagement from the individual sets of rollers or cam followers 74 and 75. As here preferably embodied, the piston rod portion 24, which will be hereinafter referred to as the piston cam 24, is provided at its free end with a set of inclined driving surfaces 80, one for each of the rollers or cam followers 74. Each such driving surface 80 may be of a contour to provide rapid angular acceleration and deceleration of the cam-follower rollers 74 at the start and finish of the linear stroke of the piston cam 24, and a substantially uniform angular velocity of the rollers 74 during the stroke. Each driving surface 80 is succeeded b y a dwell surface 82 which, in turn, is succeeded by an escape surface 84 connecting the dwell surface with the next succeeding driving surface 80. The dwell surfaces 82 parallel the reciprocal axis of the piston cam 24. Each dwell surface is of a length which is preferably slightly less than the piston stroke such that upon the piston cam 24 moving from right to left as viewed in Fig. 5, the escape surface 84 will completely uncover the cam lfollower rollers 74 at substantially the end of the stroke to permit rotation, i. e., advance, of the coupling member 60 on the torque shaft end portion 54 under the action of the restoring spring 64. It will be apparent therefore that the spacing of the driving teeth 70 of the coupling member 60, and of the driven teeth 72 of the torque shaft 53 must be commensurate with the lengths of the dwell surfaces 82 so that with the coupling member 60 held stationary by the dwell surfaces 82 in one direction of the piston stroke, the torque shaft may still be rotated by the coupling member 61 being driven by the piston rod portion 25.

The piston rod portion 25, that is, piston cam 25, is of a configuration at its free end which is identical in principle but reversed in direction relative to the piston cam 24. Thus it comprises the driving surfaces S1, dwell surfaces 83 and escape surfaces 85, all functioning with respect to the cam follower rollers to effect counterclockwise rotation of the coupling member 61 and torque shaft 53, as viewed from the left end of the device in Figs. l and 5.

In Figs. 9, l0 and ll there is depicted stages lin the relationship of the piston cams 24- and 25 to the coupling members 60 and 61, respectively in the course of one stroke of the piston. Referring to Fig. 9, it will be noted that the parts are in relative positions corresponding to those of Figs. l and 5, that is, with the piston 1 at the end of its stroke to the right as Viewed in Fig. l. Under these conditions, the piston cam 25 is in position to advance to the left to bring its driving surfaces 81 into driving engagement with the cam follower rollers 75. At the same time the dwell surfaces 82 of the piston cam 24 are in linear sliding engagement with the rollers '74 and hold the coupling member 68 against rotation on the torque shaft end portion 54. Rotation of the coupling members 69 and 6l corresponds to linear movement thereof in a direction at right angles to the stroke direction in the developed forms of Figs. 9, l0 and ll.

When the stroke is half completed, the coupling member 61 will have been caused to advance to the position shown in Fig. l0, the coupling member 6? remaining at rest as the'rollers 74 ride the dwell surfaces S2. At the completion of the stroke, the coupling member 61 will have reached the limit of its advance and be in a position corresponding to that of the coupling member 60 at the beginning of the stroke, as shown in Fig. 11. lt.

willfbe noted from iFig. 10that'at the ihalf-stroke position the rollers 74 Aare approachingtheterminuszof theidwell surfaces 182, and fthe :start Lof the .escape surfaces "84. Thus, as the stroke continues beyond .thelhalfawayzmarh the lescape xsurfaces 184 Ifnally luncover :the :rollers V74. Bearingdnmind thatlth'e advanoeioflthe coupling member -61 u"by `the piston cam I25 (has 'been .accompanied by alcorresponding advance tof the torque :shaftland that theadvance of ithe =torque v:shaft: has Lwoundeup:` the lspring 64 (-Fig. `l), `it will be ii apparent `that ;as v-soon 4as the escape surfaces iuncover -fthe :rollers L74, :the spring 64 will causeitheicouplingimemberato Aadvance relative-,to the piston cam A24 Lto the lnal eposition `shown in iFig. r11. This -relativemovementkis made Apossible by the lspacing ofltheidrivingiteeth70:andiclrivenrtceth .'72 onithecoupling member -6ll and torque shaft T53, respectively, fas above set forth. Thus, rthe ipiston 1 Ymay now :start `on Aits return ustroke during -which theudrivingsurfaces 80' of the piston cam y24 'will advance .the'rollers 74 in the same` direction 'Land distance as the .'advancefof'thearollers .75..

At lthe same time Zthe rollers 75 1will be :held-against 'the dwell surfacesSluntilthey arenncoveredby the escape surfacesfiiand soron.

In the .device 4as depicted vin Figs. :l to i8, inclusive, the Aconstruction Vand `arrangement of Ithe piston-cams and cam .follower rollers :issuch that each {stroke-ofthe piston `will effect an angular displacement-ofthe torque shaft 53 of `.ninety degrees. Thus, four strokes of \the piston are required forone revolutionV of the-torque shaft. It will be apparentithereforethat by the tuscoi Aa -relatively high pressure yworking fluid driving the piston at a relatively high speed, high torque output can be obtained at the torque shaft ends at a relative low `torque shaftR. P. M. Moreover, 4eitherend ofthe torque applicatormay be usedto apply thetorquegandfby merely reversing the applicator end-for-end, the :torque may be reversed in direction-without reversal of rotational direction of the torque shaft. p

Referring now to :the embodiment .of :this invention shown in Figs. l2 yto l5 inclusiveoflthe accompanying drawings, the torque shaft end portions 54 and 55 are provided circumferentially with helical gear portions 86 and 87, respectively. Cylindrical coupling members 88 :and 89 are of a configuration internally to provide, respectively, helical gear portions 90 and 91, respectively, in toothed engagement with the gear -portions 86 .and `87, respectively. The coupling members88 and 39 are adapted to -be driven individually, alternately, axially outwardly of the-'helical gear portions 86 and 87, respectively, by the piston 1 so as `to rotate the torque shaft by the yaction of the gear portions 90 and 91 onthe gear Aportions 86 :and 87, always in the same direction. Simultaneously with the outward driving movement of one lof the `coupling members, the other is adapted to be drawn'inwardly by the piston and restored to starting position to complete its cycle of movement. During this retraction, the coupling member being retractedis free to rotatewith the torque shaft. To this end'therefore, the coupling members 88 and 89 are provided, respectively, at their respective inner ends with `sets of ratchet teeth, 92 and 93, respectively. These sets are arranged in circular rows concentric with the cylinder axis of the coupling members.

Bearing sleeves 94 and 95, each of cylindrical contour, extend, respectively, axially of the coupling members 88 and189, respectively, and terminate at their respective'free ends in radially extending annular traction anges 96 and `97, respectively. Each of the sleeves 94 and `9S is of a length axially such that thetorqueishaft 53 will, at all times, 'oe telescopically received therewithin. 'Each sleeveis .also of an internal diameter to be in `sliding-tit bearing engagement with the torqueshaft at all times. Forlpurposes-of assembly of the torque device, the'sleeves are slotted `axiallyitolprovide sets .of spaced-.apartiexible individual fingers 98 :and 99 in the sleeves 94 andf95,

respectively. iltwillrbe apparent thatbylcircumferentially co'nstricting the'sleevesp'theeffective normaloutsideidiameter of their.respectiveztractio'n flangesmay be reduced suicientlyitolpermitdisenga'gementof theicouplingA members ifrorn 'other members, inai.fashi`onto vbe more fully explainedhereinafter.

The .tubular .piston .rod u23 tis provided with the zpair of oppositelylextending `tubular splinedrod portions `100 and =101 .wliichiterminate, respectively, .in sets -of ratchet teeth 102.and 103,;respectively. These-setsare-respcctively .of a construction rand :arrangement tto make .them complementary Lto lthe Sets iof Kratchet 4teeth 92 and `93, respectively.

The pistonLrodtportions 100-and 101 are fof an internal diameter overatdistanceiinwardly .from `the end of each to receivethe bearing=sleeves94-and `95, respectively, in annularly spaced relationship thereto, the spacing-being sufficient toiprovide a loose sliding't between-each Vrod portion and its `associated bearing sleeve. Moreover, the inner circumferential peripherylof `each 4rod `portion is -of larger'diametenover 4a relatively vnarrow circumferential strip of leach toprovide annular recesses :102' and 10S inthe rodportions 100 and 101, aespectively. The bearing sleeve retracting'anges'96 and=97` extend respectively,-intothe recesses102 and L103', respectively. The recessesareof a width axially of therod portions greater thanthe -width axially ofthe anges so as to permit of an-initial axial movementofthepiston at the `beginning of 4each stroke without an accompanying axial movement of-the'bearingsleeves.

AIn the operation 'of Lthe device of Figs. 12-13, comrnencing with `the piston in theposition shown inFig. l2, theinitial `stage of movement of-thepiston'to `the left as viewed in Fig. 12, `will effect 4disengagement of the ratchet teeth 102 ofthe piston rodporton l'fromthe ratchet teeth 92iof the coupling member 88. When fully disengaged the piston rod `portion will have moved to the left a distance sutiicientto engage the traction tlange 96 ofthe bearing sleeve 88. 'Continued axial movement of the piston rod vportion will draw the coupling member 88 to thetleft.

The same leftward-movement of thepistonthat disengages the pistonand coupling member 88 at one end will engage the' piston and .couplingfmember 89. In the engaged position the sets ofratchet'teeth-93 and 103 will be interlocked. Continued movement of the piston `to the left Awill 'result "in the coupling member 89 being moved to 'the Lleft and, since the coupling member is prevented from rotating by reason Vof its rratchet teeth, the gear'teeth l91 in engagementwith the gear teeth 87 will effect rotationvof 'the torque shaft. It'will be observed that fthis rotation of thetorque shaft is not necessarily imparted tothe coupling member 88 at the opposite end since thelatte'r is 'being advanced relative to the gear portion86 at thesame rate as Athe coupling member 89. However, it 'will `:be apparent that the coupling member 88 is capable of rotating withthe torque shaft S3 as it is moved axially by the vpiston rod portion 100. When the stroke is ,.completed, the succeeding stroke to the right, as viewed in Fig. l2, will result in the coupling member 88 driving the torque shaft through the gear portion 86, the -rotation ,being in the `same direction. Advantageously, eachistroke of the .piston will effect a quarter turnof the .torque shaft so that a relatively high piston speedis reected in .ahigh torque, llow R. P. M. of the torque shaft, rotation Yalways being in the same direction. Axial thrust 4of the torque shaft is transferred via thrust washers -104 vand 105 to .the'thrust bearings 50 and 51, respectively, at the respective opposite ends of the-.torqueunit What isfclaimedis:

Vl. A torque appliea'tordevice` comprising a rotatably mounted `torque applicator shaftpatubularpiston rod,.a piston l therefor, land ra 4cylinderttor-said piston, each con centric with said shaft, said piston rod extending in opposite directions from said piston toprovide a reciprocable double-ended drive' member; means for supplying a working `iiuid alternately to opposite faces of said piston for driving said drive member; a pair of co-axially aligned tubular bearing flanges concentric with said shaft and extending in opposite directions from the respective opposite heads of said cylinder,'said tubular bearing flanges being in splined engagement with said double-ended drive member; and, a pair of tubular coupling members concentrically mounted on said shaft for rotation relative thereto, one at each end of said drive member, :for converting linear reciprocating motion of said drive member into a uni-directional rotary motion of said shaft, said motion-converting coupling members each having means co-acting with the drive member for restraining rotation of the coupling member in one direction of movement of the drive member, and said coupling members having means on each coactingwith the torque applicator shaft for rotating said torque applicator shaft in response to reciprocation of said drive member. Y

2. A torque applicator device' comprising a rotatably mounted torque-applicator shaft having provision at each of its ends for coupling the shaft to an object to be rotated; a double-ended drive member mounted for linear reciprocation in a path parallel to the rotational axis of said shaft; and, a pair of tubular coupling members concentrically rotatably mounted on said shaft, one at each end of said drive member, for converting linear reciprocating motion of said drive member into uni-directional motion of said shaft, the mounting of each coupling member on said shaft being such as to enable relative rotation of shaft land coupling member only in one direction of movement of the drive member, said coupling members having means on each coacting with the torque applicator shaft for rotating said torque applicator shaft in response to reciprocation of said drive member.

3. A torque applicator device comprising a rotatably mounted torque applicator shaft; a cylinder concentric with said shaft; a piston in said cylinder, said piston having a tubular piston rod extending in opposite directions from said piston to provide a reciprocable double-ended drive member; means for supplying a Working uid alternately to opposite faces of said piston for driving said drive member; a pair of motion-converting tubular coupling members concentrically rotatably mounted on said shaft, one at each end of said drive member; means on each end of said drive-member engageable with the associated coupling members for restraining rotation of said coupling members alternately on successive strokes of said drive member; and, means on each coupling member for rotating said torque applicator shaft in response to reciprocation of said drive member.

4. A torque applicator device comprising a rotatably mounted torque applicator shaft, said shaft being of a configuration to provide a central portion and a pair of lesser diameter end portions, one at each end of the central portion, and said center portion having `at its ends a pair of circular rows `of driven teeth, one row at each end; a tubular piston rod slidably mounted on said central portion, a piston therefor, and la vcylinder for said piston, each concentric with said shaft, said piston rod extending in opposite directions from said piston to provide with said piston a reciprocable double-ended drive member, the respective opposite ends of said drive member being of a configuration to provide at each of its ends la set of camming surfaces; means for supplying a working fluid alternately to opposite faces of said piston; a pair of motion-converting coupling members journalled on said lesser diameter end portions, one on each, for converting linear reciprocating motion of said drive member into a unidirectional rotary motion of said shaft, said coupling members each having a coaxial recess in the end thereof Iadjoining said central portion, a set of cam followers to be driven by the set of camming surfaces at the associated end of said piston rod, yand a circular row of driving'teeth at its recessed end, said driving teeth extending into the intertooth spaces of the opposingrow of driven teeth on said torque shaft, the spacing of the driving and the driven teeth in each of said krows being suiiicient to permit limited angular displacement of the torque shaft relative to the coupling membersalternately on successive strokes of the piston and, Y'a pair of'r'esilient means, one in each of said coaxial recesses, connecting said coupling members to said torque shaft, for restoring the respective coupling members to their starting positions relative to said torque shaft.V

5. The device of claim 4 in lwhich each end of said drive member is providedwith four sets of camming surfaces and each of said coupling members is provided with a set of four cam followers. v6. The device of claim 5 in which each camming surface comprises an inclined driving surface, a dwell surface and an escape surface connecting the dwell surface with the next succeeding driving surface, said dwell surface paralleling the reciprocal axis of the torque shaft.

7. The' device of claimv 'in which the cam followers of each set are in the form of rollers arranged in pairs of diametrically opposed rollers, the pairs of the set being `equally angularly offset from each other and the rollers being journalled individually on individual axles carried xed by the coupling member.

8. A torque applicator device comprising a rotatably mounted torque applicator shaft, said shaft being 'of a coniiguration to provide a central portion and a pair of lesser diameter end portions, one at each end of the central portion, and said center portion having at its ends a pair `of circular rows of driven teeth, one row at each end; a tubular piston rod slidably mounted on said central portion, a piston therefor, and a cylinder for said piston, each concentric with said shaft, said piston rod extending in opposite directions from said piston to provide with said piston a reciprocable double-ended drive member, the respective opposite ends of said drive member being of la configuration to provide at each of its ends a set of camming surfaces; means for supplying a working iiuid lalternately to opposite faces of said piston; a pair of motion-converting coupling members journalled on said lesser diameter lend portions, one on each, for converting linear reciprocating motion of said drive member into a unidirectional rotary motion of `said shaft, said coupling members each having a set of cam followers to be driven by the set `of camming surfaces at the `associated end of said piston rod, and a circular row of driving teeth extending into the intertooth spaces of the opposing row of driven teeth on lsaid torque shaft, the spacing of the driving and the driven teeth in each of said rows being suiicient to permit limited angular displacement of the torque shaft relative to the coupling members alternately on successive strokes of the piston and, a pair of resilient means, one for each of said coupling members, lconnecting said coupling members to said torque shaft, for restoring the respective coupling members to their starting positions relative to said torque shaft.

9. A torque applicator device comprising a rotatably mounted torque applicator shaft, said shaft being of a configuration to provide a central portion and a pair of lesser diameter end portions, one at each end of said central portion, each provided circumferentially with a helical gear portion; a tubular piston rod slidably mounted on said central portion, a piston therefor, and a cylinder for said piston, each concentric with said shaft, said piston rod extending in opposite directions from said piston to provide with said piston a reciprocable double-ended drive member, the respective opposite ends of said drive member being of a configuration to provide at each of its ends a set of ratchet teeth; means for supplying a Working iiuid alternately to opposite faces of said piston; and, a pair of tubular motion-converting coupling members mounted on said lesser diameter end portions concentrically `thereof, one on each, for converting linear reciprocating motion'of :said drive member into a vunidirectional rotary motion of rsaid shaft, said coupling members being each of a configuration to provide internally a helical gear portion in toothed engagement with the helical gear portion of its associated lesser diameter end portion, having each a set of ratchet teeth complementary to the ratchet teeth at the associated end of said drive member, and having each a traction means coupled to saiddrivemember forlimited axial movement relative thereto.

l0. The device of claim 9 in which each said coupling member comprises atbearing sleeve at the ratchet end thereof, said sleeve terminatingin said traction means.

l1. The device of claim lOin which said traction means is a radially extending annularange.

12.` The device of claim `9 in which said drive member is provided `at each of its ends with `an annular recessin its inner circumferential surface, `andeach said vtraction means is interlocked with said drive member in saidy to iprovide an annlar groove, `and .in which :each said eonplingmembers comprises an axially :extending sleeve at zits'ratchetfend andtans annular :traction flange at .the free :end of `saidzsleeve, each said flange `extendinginto the `annular recess in :the associated end `of vsaid ,drive member `and :each saidf recess `being tdimensioned axially olsaidadrive:memberitoiprovidezfor limited axial :relative movementbetweensaid drive `member and saidcoupling members'.Y

114. The devicelof claim -13 in which said sleeves are each Tof; aninternalY diameter such that `they are in slidingt bearing `*engagement `With said torque applicator shaft and in @which ,each said sleeve comprises aset of spacedapart exible 'individual lingers.

References .Cited in `.the lue of this patent UNTEED `STATES ePATENTS 95,586 LHenderson Oct. 5, 1'869 1,089,408 Ganderton Mar. 10, `1914 l,l^67,l79 Hires Jan. 4, 1916 :FOREIGN .PATENTS 380,938 5Italy e lune 13, .1940 

